1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

3K stutter

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Old Mar 6, 2007 | 10:36 PM
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3K stutter

for starters, i did do a search but nothing came back as a similar problem to what i'm having. on my 82 GSL, the engine stutters and the engine doesn't like much throttle at 3K. if i am accelerating gradually rather than getting into it, the problem is not as bad. over 3K the power is smooth, however, at times it feels as if the engine bogs and other times above 3K, the engine pulls very strong. i replaced the plugs(NGK), rotor, leading ignitor, and fuel filter prior to this problem. the engine idles well. what can cause this problem?
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Old Mar 6, 2007 | 10:50 PM
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Stock exhaust with cats or not?
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Old Mar 7, 2007 | 04:47 AM
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stock exhaust with all cats. small leak between the maifold and the monolith converter. no split ait pipe(though i have one and am going to install it hopefully this weekend).
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Old Mar 7, 2007 | 05:56 AM
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I had a similar problem with my 1985. I replaced the carb gaskets that are on the intake and checked for any vacuum leaks around the carb area.
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Old Mar 7, 2007 | 11:48 AM
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Could be a restriction in the carb? Maybe shoot some Seafoam through the tank and see... Otherwise, clogged jets or a weak fuel pump? Have you checked the timing?
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Old Mar 7, 2007 | 03:28 PM
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timing is ok. i think i'll pick up some seafoam and throw some in the tank. my guess is that the jets are partially clogged with varnished gas.
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Old Mar 7, 2007 | 05:37 PM
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ok, i re-assesed. when taking off from a stop, between 1300K and 2700K the engine bogs and wants to stall. the car will accelerate from a stop just fine after bogging initially before 3K. i looked int the carb and the rear primary brass(i apologize, i dont know the exact name of the part) was spraying at what i thought to be a nice flow of fuel and the front-most primary brass was spraying inconsistent patterns of fuel. hope this helps.
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Old Mar 8, 2007 | 03:09 AM
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Sounds like a clogged jet...
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Old Mar 8, 2007 | 04:46 AM
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well, what do you guys think about the seafoam in the tank idea? i think thats my best alternative at this point this side of rebuilding the carb.
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Old Mar 8, 2007 | 09:23 PM
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how much seafoam do you guys reccomend using in the tank to clean the carb and how often should i use the stuff in the tank? on my piston engine cars i ususlly suck the seafoam into the engine through a vaccume line. this time, its going in the tank so i'd like to get some info before i go and ruin something.
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Old Mar 8, 2007 | 10:03 PM
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Kentetsu is the resident spokes person for Seafoam. I'm surprised he has not chimed in with this opportunity.

When I use Seafoam, I put it in the whole bottle with a 1/4 tank or less and run it until I am almost empty.
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Old Mar 9, 2007 | 04:50 AM
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Old Mar 9, 2007 | 04:54 AM
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well, with that said, i have a half a tank and 1/4 bottle of seafoam left. so, today i'll buy another bottle of seafoam and put it in the tank and put what i have left in the tank. i know its good stuff and i really hope it helps unclog that jet
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